PB2459: AFTER ALLOGENEIC HAEMATOPOIETIC STEM CELL TRANSPLANTATION OUTCOMES OF HAEMATOLOGIC MALIGNANCIES COMPLICATED BY AUTOIMMUNE DISEASES
Authors: Ying Kang, Chencong Wang, Haixia Fu, Yuan-Yuan Zhang, Feng-Rong Wang, Xiao-Dong Mo, Yuqian Sun, Chen-Hua Yan, Yu Wang, Lanping Xu, Xiao-Jun Huang, Xiao-Hui Zhang
Journal: HemaSphere (2023)

Topic: 22. Stem cell transplantation - Clinical Background: Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is an established treatment for haematologic malignancies and non-malignant diseases. There is considerable evidence to suggest that there is an increased occurrence of haematologic malignancies in patients with autoimmune diseases(AD) compared to the general population, with a further increase in risk after exposure to cytotoxic therapies. In contrast to conventional immunosuppressive medication and biologicals, HSCT offers the prospect of long-term AD remission. Most HSCT procedures in autoimmune disease involve autologous stem cells. In the case of allogeneic transplantation, allogeneic HSCT has curative potential,but carries significant risks of rejection and graft-versus-host disease. Aims: We aimed to investigate the clinical features, risk factors, and outcome of haematologic malignancies in patients with autoimmune diseases after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Methods: From May 2005 to April 2022, we conducted a retrospective, case-control study of 6570 consecutive patients who underwent allo-HSCT. Lastly, 38 haematologic malignancy patients with autoimmune diseases following allo-HSCT were identified and included in the case group. For each case, individual matching was used to select 3 control subjects at random from the same cohort who had no autoimmune diseases based on the following matching criteria: follow-up time (±6 months)and time of HSCT (±3 months). Results: Among the 38 patients with autoimmune diseases, there were 16 males (42.1%) and 22 females (57.9%). The median age was 43 (16-65) years old. There were 114 patients with haematologic disease but without autoimmune diseases, including 79 males (69.3%) and 35 females (30.7%). The median age was 36 (17-65) years old. With a median follow-up of 803 days, the cumulative incidences of CMV viremia in the cases and controls were 63.2% and 71.1%, respectively. No significant difference in the development of CMV viremia was identified between the 2 groups (P =0.362). The cumulative incidence of acute GVHD was 70.2% in the control group, which was higher than the 57.9% incidence of acute GVHD observed in the case group, although the difference was not significant (P =0.377). In the case and control groups, the cumulative incidences of chronic GVHD were 70.3% and 64.9%, respectively(P=0.783). In the control and case groups, the OS percentages were 82.2%± 0.08% and 75.5%± 0.14%, respectively (P = 0.643). The 1-year leukaemia-free survival rates (LFS) were 80.8% ±0.07% and 73.1% ±0.14%, respectively (P = 0.553). The 1-year cumulative recurrence rates (CIRs) were 6.59% ±0.01% and 5.57% ±0.03%, respectively (P = 0.342). The 1-year transplant-related mortality (TRM) rates were 12.86% ±0.02% and 24.76% ±0.01%, respectively (P = 0.17), the 2-year transplant-related mortality (TRM) rates were 16.67% ±0.03% and 28.24% ±0.01%, respectively,and there was no significant difference between the two groups. The results from the univariate analysis revealed that the associations between patients with autoimmune diseases and age, cell count of CD34 cells at transfusion, ABO compatibility, stem cell sources, engraftment time, aGVHD, and cell count of mononuclear cells at transfusion were insignificant. Sex had a strong impact (P <.05). In the multivariate analysis, there were unidentified independent risk factors for patients with autoimmune diseases. Summary/Conclusion: The patients with autoimmune diseases had lower OS, LFS, and CIR and higher TRM than the control group. Keywords: Allogeneic hematopoietic stem cell transplant, Autoimmune disease, Prognosis